This script and its contents are not associated with the VASP code in any way. Use them at your own risk and reward.

The basic flow of the script is this:

  1) Geometry optimisation
    1a) Optimise coordinates
    1b) Optimise the cell 
    1c) Optimise everything together
    
  2) Calculate the polarisation of the cell - if non-centrosymmetric, uisng a Berry phase approach
  
  3) Calculate the band structure
    3a) Get the self-consistent charge distribution uisng the standard k-points
    3b) Set up the special k-point mesh and calculate the band-structure non-self-consistently
    
  4) Calculate the optical properties and high-frequency dielectric constant
  
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What you need to set:
  All INCARs : set NPAR/KPAR to best work with your system, Peter Larsen has an excellent blog on this (https://www.nsc.liu.se/~pla/)
  KPOINTS for optimisations/charge calculation should be specicied in the usual way
  KPOINTS for band structure - these must be set up in an individual file called KPOINTS.band. This file contains only the special points with their weighting
  eg.   0.0000  0.50000  0.00000   0.00    
  if you use ASE I have written a script to generate these 'automatically' (https://github.com/keeeto/kpoints-brillouin/blob/master/kpoints-bz-vasp.py)
  KPOINTS for the optics, this should be denser than the regular KPOINTS, if possible
  POTCAR containing the pseudopotentials